Because such applicator rollers are composed of elastic material at their circumference, a gap that is wedge-shaped in the vertical plane is created on both sides of the board-like material to be coated; with time, this gap becomes plugged with coating material and causes, for example, uneven application in the area of the periphery of the boards.
An apparatus of this type is disclosed in German Utility Model No. 85 03 321. In this device, the applicator rollers are provided with strippers which produce coating-free edges on both sides of the boards to be coated. Even then, however, at places where the board in its passage does not pick up coating material, the material still accumulates on the rollers and this problem is not satisfactorily overcome in this apparatus.
Strippers also have the disadvantage of being in direct contact with the applicator rollers and pressing into the elastic surface coating of, for example, rubber, thus shortening the service life of the applicator rollers. This is a particular disadvantage when boards having various widths are to be processed with the same applicator rollers.